It's still very early to detect a heartbeat- not everyone can at that stage even if your dates are correct. Re the Foetal pole I'm not sure to be honest. But overall it is still very early and normally you'd need a very high tech ultrasound device to pick up much detail at all at 6 or even 7 weeks - I'm not sure what the army hospital facilities are like in Korea; how up to date they are compared to Australia or the US.